Numbers 11:27

And there ran a young man From the camp to the tabernacle, who had heard Eldad and Medad prophesy; which he thought was not right, being done without the knowledge and approbation of Moses, and in a private tent in the tabernacle, not among the elders, but the common people: who this young than was is not material to know; some of the Rabbins, as Jarchi says, affirm he was Gershon the son of Moses; whoever he was, no doubt, it was with a good design, consulting the glory of God and the honour of Moses, and therefore in great haste ran to him with the information:

and told Moses, and said, Eldad and Medad do prophesy in the camp; who seem by this, to be persons well known, and of some note and figure; since not only the young man could call them by their names, but there needed no other description of them to Moses and those with him.